Boston Marathon bombings suspect Dzhokhar Tsarnaev faced more than two dozen survivors of that attack Wednesday as he pleaded not guilty to killing four people and wounding more than 200.

Tsarnaev is charged with 30 federal counts stemming from the April 15 attack, when a pair of bombs went off near the finish line of the packed course. Three people died in the blasts, including an 8-year-old boy, while a Massachusetts Institute of Technology police officer was killed three days later at the start of the dramatic chase that led to Tsarnaev's capture.

MIT police lined up outside the courthouse as the hearing neared its end Wednesday afternoon in a show of solidarity with their fallen comrade, Sean Collier. Inside, about 30 survivors of the attack watched as Tsarnaev appeared before U.S. Magistrate Judge Marianne Bowler.

It was the first time he had been seen in public since his arrest. The 19-year-old was dressed in an orange jail jumpsuit, his hair long and shaggy, his left arm in a cast. He was wounded in the pursuit -- during which his brother, Tamerlan, was killed -- and he appeared to have an injury to the left side of his face.

Tsarnaev looked back at the spectators in the packed courtroom before entering his plea -- and to Liz Norden, whose two sons each had a leg amputated after the attacks, he appeared to smirk.

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Boston: The aftermath of terror 21 photos

Boston: The aftermath of terror21 photos

Boston: The aftermath of terror – A young runner, left, stops by a Boston church blocks away from the scene of the bombings. The blasts exploded near the Boston Marathon's finish line on Monday, April 15, killing three people and injuring more than 170 others. See all photography related to the Boston bombings.

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Boston: The aftermath of terror21 photos

Boston: The aftermath of terror – Unclaimed finish line bags litter the ground near the bombing sites. A day after the terror attack, authorities warned city residents to keep their guard up amid a massive investigation into the bombings.

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Boston: The aftermath of terror – Investigators work at an area of the crime scene on Boylston Street on April 16.

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Boston: The aftermath of terror – Blood is visible on a sidewalk in front of a Boston store on April 16.

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Boston: The aftermath of terror – Flowers rest against a police barricade down the street from the Boston Marathon's finish line on April 16.

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Boston: The aftermath of terror – Unused thermal blankets for runners are piled high near the scene of the bombings on April 16.

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Boston: The aftermath of terror – National Guardsmen look out from inside Boston's Back Bay Station on April 16.

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Boston: The aftermath of terror – U.S. military Humvees move down deserted Boylston Street on April 16.

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Boston: The aftermath of terror – National Guardsmen patrol the Back Bay Station on April 16 as security remains tight in Boston.

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Boston: The aftermath of terror – Pedestrians pass National Guard troops at a roadblock on April 16.

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Boston: The aftermath of terror – The unfinished meals of fleeing customers are left on tables at an outdoor restaurant in Boston on April 16.

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Boston: The aftermath of terror – People congregate at a security gate near the blast scene on April 16.

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Boston: The aftermath of terror – A man jogs down a street near the scene of the bombings on April 16.

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Boston: The aftermath of terror – A woman sits alone at a Boston cafe on April 16.

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Boston: The aftermath of terror – A woman carries a sign she made to support her runner husband near the scene of the bombings.

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Boston: The aftermath of terror – A police officer stands on duty in Boston on April 16.

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Boston: The aftermath of terror – People have breakfast at a Boston cafe on April 16.

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Boston: The aftermath of terror – A Boston police officer stands near blast sites April 16.

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Boston: The aftermath of terror – National Guard troops man a roadblock April 16.

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Boston: The aftermath of terror – A Boston police officer is heavily armed blocks away from the scene of the bombings.

Callan said Tsarnaev's lawyers could argue that he was under the "mesmerizing influence" of Tamerlan, his older brother. But Callan believes one piece of evidence will make it easy for prosecutors to shoot down that argument: While he lay bleeding in the motorboat, covered with a tarp, the younger Tsarnaev apparently scrawled his motive for his alleged deeds onto its sides.

"The U.S. Government is killing our innocent civilians," it read. "I can't stand to see such evil unpunished."

"We Muslims are one body, you hurt one you hurt us all."

"Now I don't like killing innocent people it is forbidden in Islam but due to said (unintelligible) it is allowed."

"That would indicate that he was not under his brother's influence, that he had an independent thought process and dedication to this movement on his own," Callan said.

Prosecutors will use the writings to argue intent -- that Tsarnaev knew what he was doing.

Indictment blow by blow

Tsarnaev is charged with killing three spectators in the bombings and a MIT police officer ambushed in his cruiser a few days later. He also is accused of "maiming, burning and wounding scores of others," U.S. Attorney Carmen Ortiz has said.

But that is merely a handful of the charges.

Add to those use of a weapon of mass destruction resulting in death, deadly bombing of a public place, use of a firearm during a crime of violence causing death, carjacking, bodily harm. The list goes on.

The indictment details the planning that allegedly went into the attacks. Tamerlan Tsarnaev bought 48 mortars, it says.

It also says that Dzhokhar Tsarnaev downloaded a copy of Inspire magazine, which included instructions on building IEDs using pressure cookers and explosive powder from fireworks.

Pressure cooker bombs were used in the Boston Marathon attacks.

Three days after the attacks, on April 18, the FBI released photographs of the brothers, identifying them as bombing suspects.

Hours later, they drove their Honda Civic to the MIT campus, where they shot and killed Collier and attempted to steal his service weapon, the indictment says. They were allegedly armed with five IEDs, a Ruger P95 semiautomatic handgun, ammunition, a machete and a hunting knife.

The indictment alleges that late that night, the brothers carjacked a Mercedes in Boston using guns.

Soon after, police discovered the Tsarnaevs at an intersection in nearby Watertown, where they tried to apprehend them, but the brothers fired at the police and used four IEDs against them, the 74-page indictment alleges.

Police tackled the elder brother and were trying to handcuff him when Dzhokhar Tsarnaev got back into the Mercedes and drove it at the officers, according to the indictment. He wound up running over his brother, "contributing to his death."

The younger Tsarnaev escaped, abandoned the car nearby and hid in the boat, where he remained until the owner noticed him and called police.